Manufacturers of battery powered devices typically face a challenge of making their designs compatible with many battery disparate technologies that offer supply voltages ranges differing in their provided maximum, nominal, and minimum values. Moreover, whatever the chosen battery technology is, there is a desire for the battery to deliver its complete energy capability to the load and that the battery's energy capability be exploited with high efficiency, without leaving useful energy in the battery cells. This situation has led in time to batteries offering a wider and wider output voltage range, so that the battery's output voltage during the discharge phase can be higher and in the same range or even much lower than the minimum voltage that the load can accept. This desire goes together with increasing demands that the end-user applications be powered for longer durations. Hence, one aspect of end-user satisfaction is using the energy of the battery down to the last erg while avoiding energy loss thereby increasing energy conversion efficiency.